Abstract: A fluid transfer valve has ports arranged in groups. The valve has a rotor having channels and an actuator is operably connectable to the rotor. The actuator is positionable in a loading orientation in which the first channel is connected to one or two of the ports to transfer fluid into the first channel and/or the second channel is connected to one or two of the ports to transfer a second fluid into the second channel. The actuator also is positionable into first and second injection orientations in which various ones of the channels and ports are connected for different fluid flow configurations. Each channel has two ends located on a virtual circle whose center coincides with the rotor's axis of rotation. The channels can have a semicircular shape, a semi-oval shape or a U-shape. An analytical system and method that use the inventive valve are also disclosed.

Abstract: The invention relates to methods for investigating mixtures of substances by capillary electrophoretic separation, in particular of biopolymers such as proteins, proteoglycanes or other protein conjugates, or their digestion peptides. The invention comprises the analysis of specific, well-separated substances of analytical interest found in complex mixtures by subjecting the mixture of substances together to a selective derivatization process using charge-carrying groups prior to the electrophoretic separation, so that the substances of interest can be detected, essentially alone, within a specified time window.

Abstract: The invention relates to methods used for mass spectrometric analysis of substances separated by capillary electrophoresis, in particular biopolymers such as proteins, proteoglycanes or other protein conjugates or their digest peptides. The invention consists in reducing the electrophoresis voltage upon appearance of the first analytically interesting substance, thereby maintaining the high separation power and gaining sensitivity. With direct coupling, e.g. by electrospray, the electrophoretic voltage may be directly controlled by the ion current measured by the mass spectrometer.